Hydraulic break fuse requiring reset



June 19, 1956 R. STEVENSON 2,750,956

HYDRAULIC BREAK FUSE REQUIRING RESET Filed April 2, 1952 ll 83 17 6O 44 64 9O 38 M 3+ 3| 32 \K \KW XQ iii/77W E 1 IZ V H flaw/1W5! Ll 5o\8\ 4z\\ 35,0 47 2| 8415 T8 70 48 39 43 45 36 5| I I 7828377756 0217267648749 44342 8740 35141334 33 3| 32 \\\\\\\\\\Y1/ f/ r F 5 IE. y,

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INVEN TOR. ROBER T STEVENSON ATTORNEY United States Patent HYDRAULIC BREAK FUSE REQUIRING RESET Robert Stevenson, Barrington, R. I., assignor to Anco, Inc., a corporation of Rhode Island Application April 2, 1952, Serial No. 280,097

2 Claims. (Cl. 137-460) This invention relates to hydraulic break fuses and more particularly to a fuse in a fluid pressure system which will prevent the bleeding of the hydraulic fluid from the system, when a break occurs in a line of the system.

A principal object of the present invention is to provide a fuse in a fluid pressure system which will become operative when a surge in the fluid pressure, due to a leak, rupture or break in the system, reaches the fuse.

Another object of the present invention is to provide a positive operating, foolproof, inexpensive break fuse for a hydraulic pressure system which will prevent the system from becoming totally disabled when a leak, rupture or break occurs in the system.

Still another object of the present invention is to provide a fuse of novel construction, which is automatic in operation and which requires no attention when in service.

And still another object of this invention is to provide a break fuse which will shut off the flow of hydraulic fluid the instant a differential in pressure of the fluid reaches the break fuse.

This invention has particular adaptation to hydraulic pressure systems used on automobile brakes, machine tools, landing gear of an airplane, airplane wing flaps, bomb bay doors and other hydraulically operated airplane parts which are subjected to sudden shock or damage caused by bullets.

The present invention was created to increase the efliciency of operation or to reduce the cost of manufacture of a hydraulic break fuse.

Other objects of the present invention will become apparent in part and be pointed out in part in the following specification and claims.

In the accompanying drawings wherein like reference characters refer to like parts, I have shown a preferred embodiment of the present invention. However, I do not limit myself to the exact showing because changes can be made without departing either from the spirit or the scope of the present invention.

Figure 1 is a longitudinal sectional view of the new and improved hydraulic break fuse showing the piston in inoperative position.

Figure 2 is a view similar to Figure 1, showing the piston and other parts in operative position.

Figure 3 is a side elevational view of the present invention.

Figure 4 is a right hand end view of Figure 3.

Referring to the drawings wherein is shown a novel construction of the present invention, reference character generally indicates the hydraulic break fuse assembled. The body 11 consists of a cylinder having threaded areas 12 and 13, internally on opposite ends, thereof. Adjacent the base of threads 13 is a circular recess 14 provided in accordance with good manufacturing practices. A chamber 15 in cylindrical body 11 extends from circular recess 14 to a face 16 of an abutment 17 which contains a piston seat 18 and a passageway 20. The beveled face 24 formed in abutment 17 is provided to accommodate a class of fitting prevailing in the hy- 2,750,956 Patented June 19, 1956 ice draulic industry. The base 25 of threads 12 may be manufactured with a different contour to accommodate a different type of fitting.

A gland 30 provided with an hexagonal shoulder 31 at its greatest diameter is provided with external threads 32 on its reduced outside diameter. Threads 32 will form a connection with the line of a hydraulic system. A relief ring 33 adjacent hexagonal shoulder 31 is the termination of threads 34 adapted to engage threads 13 of body 11. A recess 35 in the outside diameter of gland 30 is adapted to accommodate a fluid tight packing, illustrated by way of example as consisting of an O ring 36 which cooperates with the wall 22 of chamber 15 to form a fluid tight seal. Recess 35 divides the outside diameter of gland 30 into ring 37 and shoulder 38 which is provided with pin retaining areas 40 and 41. A neck 42 projects from shoulder 38. It is provided with a recess 43 and ports 44, 39 and 45. A nipple 46 projects from neck 42.

Internally, gland 30 is provided with a centrally located passageway 47 which terminates in a restricted bore 48. A wall 50 is formed at the junction of passageway 47 and bore 48. A bell mouth 51 is provided in the outboard end of passageway 47 to accommodate a clas of fitting prevailing in the hydraulic industry. Any other shape may be provided in place of bell mouth 51 to accommodate a fluid tight fitting of another choice.

A piston 60 provided with a sleeve 61 which terminates in a well 62 has a wall 63 formed at the juncture of sleeve 61 and well 62. Sleeve 61 is provided with recess 64 which are formed in its face and which connects with ports 67, 68 formed in circular wall 70. It is understood the number of ports may vary in accordance with the area of flow desired. Four are herein contemplated. One set Of ports is not shown due to the nature of the drawings. A face 59 is formed at the base of well 62. V

Externally piston 60 comprises a major diameter 72 terminating in a projection 73 provided with pin receiving orifices 74 and 75 on one side and with a piston face 76 on the other end. Piston face 76 is provided with a recess 77 adapted to house a fluid tight packing of any commercial product but illustrated tobe an O ring 78 which forms a fluid tight seal when cooperating with piston seat 18.

A spring 84 has one end against base 23 and the other end in spring seat 71. Spring 84 acts to retain piston 60 in inoperative position which is the position designated when piston face 76 is not engaging piston seat 18.

Pins 87, 88 are secured in pin retaining areas 40, 41 and are designed to slidably fit in pin receiving orifices 74, 75 so that the ends of pins 87, 88 will abut face 90 of piston 60 when piston 60 is in operative position with piston face 76 engaging piston seat 18.

In operation the new and improved hydraulic break fuse functions as follows: Threads 12 will be connected to the downstream side of the line. Threads 32 will be connected to the upstream side of the line. The hydraulic fluid therefore flows from right to left as viewed in the drawings. Referring to Figure 1, hydraulic fluid under pressure will enter passageway 47 and flow into restricted bore 48 and act on face 59. Nipple 46 will remain in well 62 so long as the hydraulic fluid under the same pressure as the pressure acting on face 59 is flowing through ports 44, 45, 39, recess 43, recess 64, ports 67, 68 into chamber 15, past piston seat 18 and passageway 20 on into the outlet conduit. Just as soon as the pressure acting on face 59 exceeds the tension of spring 84 as it will when a surge in pressure passes through passageway 47 into restricted bore 48, piston face 76 will engage piston seat 18. O ring 78 will engage piston seat 18 thereby forming a fluid tight seal and preventing the free flow of hydraulic fluid from chamber into passageway and beyond. As piston 76 engages piston seat 18, pins 87, 88 will pass out of pin receiving orifices 74, 75 and drop down behind face 90, thereby preventing spring 84 from forcing piston face 76 out of engagement with piston seat 18.

Having shown and described by way of example a preferred embodiment of the present invention but not wishing to limit myself to the exact construction shown because structural changes can be made without departing from the spirit or scope of the invention.

What I claim is:

1. A hydraulic break fuse consisting of two oppositely disposed cylinders forming an inlet passageway and an outlet passageway respectively and united in fluid tight relationship to form a continuous passageway, means on opposite ends of said cylinders to be united with a hydraulic conduit, one cylinder in its continuous passageway having a chamber and a piston seat, the other cylinder having a shoulder, a neck projecting from said shoulder, a multiple number of ports in said neck, a nipple extending from said neck, a plurality of pins fixed in said shoulder, said continuous passageway having a restricted bore through said nipple, said ports forming an extension of said inlet passageway, a piston having a sleeve terminating in a well, externally said piston comprises a major diameter portion having a projection provided with a plurality of pin receiving orifices adapted to engage and disengage said pins fixed in said shoulder and a piston face housing a fluid tight packing, a multiple number of ports in said major diameter portion adapted to register with said multiple number of ports in said neck, said piston face and packing being adapted to engage and disengage said piston seat, said well being adapted to engage and disengage said nipple, resilient means located in said piston seat abutting the end of said piston, fluid entering said restricted bore from said inlet passageway acting on the base of said well to overcome the tension of said spring and force said piston face into engagement with said piston seat and said plurality of pins being constructed and arranged to abut said projection of said major diameter portion when retracted from said pin receiving orifices to retain said piston face in engagement with said piston seat.

2. A hydraulic break fuse consisting of a body having axially thereof, a passageway comprising a chamber,

an outlet port an inlet port and a piston seat intermediate said chamber and said outlet port, a gland having means united in fluid tight relationship with said body and having externally thereof a shoulder located in said chamber, a neck adjacent said shoulder, a nipple adjacent said neck, a plurality of pins fixed in said shoulder and projecting beyond said shoulder and substantially parallel with said neck, a multiple number of ports in said neck, said gland having axially thereof an inlet port in communication with said chamber through said ports, a piston provided axially with a sleeve and a well adjacent said sleeve slidably mounted upon said neck and nipple respectively, externally said piston is provided with a major diameter portion having a projection with a plurality of pin receiving orifices, engageable and disengagable with said pins, said pins being constructed and arranged to abut the major' diameter portion when withdrawn from said orifices, a multiple number of ports in said major diameter portion, adapted to register with said multiple number of ports in said neck and a piston face provided with means to form a fluid tight seal with said piston seat and resilient means located in said piston seat abutting the end of said piston face, a continuous fluid passageway being provided from said inlet port to said outlet port when said piston is under the influence of said resilient means and said continuous fluid passageway being interrupted by said piston and the pins retracted from said orifices when the force of the fluid in said inlet passageway acting on the base of said Well overcomes the force of said resilient means to place said piston face in engagement with said piston seat.

References Cited in the file of this patent UNITED STATES PATENTS 860,914 Haley July 23, 1907 2,024,042 lance Dec. 10, 1935 2,069,022 Sisk Jan. 26, 1937 2,127,849 Stone Aug. 23, 1938 2,245,271 Guill June 10, 1941 2,358,228 Hoof Sept. 12, 1944 2,411,392 Saville Nov. 19, 1946 2,439,116 Waterman Apr. 6, 1948 2,451,626 Marshall Oct. 19, 1948 2,554,390 Stevenson May 22 1951 

